Method and apparatus for forming an article from pulped material

Abstract

Method and apparatus for moulding an article from pulp material, in which the article is moulded on the surface of a mould tool, the article is pressed and the pressed article is dried, using heated gas or superheated steam that is passed through the pressed article or using microwaves, in which the pressed article is retained on a tool during the drying. The tool may be the mould tool or a different tool.

1 . A method for forming an article by moulding of a pulp material comprising:
 moulding the article on the surface of a mould tool;   pressing the moulded article; and,   passing heated gas or superheated steam through the pressed article whilst the pressed article is retained on a tool.   
     
     
         2 . The method of  claim 1 , wherein pressing and the passing of heated gas or superheated steam through the article is carried out whilst the article is retained on the mould tool, or on another tool onto which the article has been transferred. 
     
     
         3 . The method of  claim 1  or  claim 2 , further comprising at least one further treatment step to finish the article and/or to remove additional water from the article. 
     
     
         4 . The method of  claim 3 , wherein the at least one further treatment step comprises subjecting the article to microwave energy. 
     
     
         5 . The method of  claim 1 , wherein the pressing step comprises a plurality of pressing steps. 
     
     
         6 . The method of  claim 5 , wherein subsequent pressing steps are used to apply successively increasing pressure to the article. 
     
     
         7 . The method of  claim 1 , wherein pressing the moulded article comprises using a press tool or tools and wherein the press tool or tools are not heated. 
     
     
         8 . The method of  claim 1 , wherein the pressing step includes applying pressure to an inboard portion of the article, and gradually applying pressure outwardly to outer portions of the article. 
     
     
         9 . An apparatus for forming an article, the apparatus comprising:
 a mould tool onto which pulp material is coated to form the article;   a press tool for pressing the moulded article;   a source of heated gas or superheated steam; and   a drying tool on which the pressed article is retained and through which the heated gas or superheated steam is passed.   
     
     
         10 . The apparatus according to  claim 9 , further comprising a microwave drying tool on which the article is retained after being treated with the heated gas or superheated steam and an associated source of microwave energy for applying microwave energy to the article. 
     
     
         11 . The apparatus according to  claim 9 , further comprising a source of microwave energy provided to apply microwave energy to the article when not on a tool. 
     
     
         12 . The apparatus according to  claim 9 , in which a single tool is used as the mould tool, press tool, drying tool and/or, where provided, a microwave drying tool. 
     
     
         13 . The apparatus according to  claim 9 , in which the tool or tools are formed as mesh tools, sintered tools, such as a sintered ceramic or bronze tool, or as perforated tools, for example a perforated aluminium tool. 
     
     
         14 . The apparatus according to  claim 9 , in which the press tool includes at least one flexible mould surface behind which fluid can be injected to apply pressure initially in the region of the mould surface close to the point or points at which the fluid is injected, the region of the mould surface over which pressure is applied being expanded as fluid continues to be injected. 
     
     
         15 . The apparatus according to  claim 14 , in which the flexible mould surface is formed over a solid backing member, with the fluid being injected into the space between the flexible surface and the backing member. 
     
     
         16 . The apparatus according to  claim 15 , in which the flexible surface is formed as a sheet, or as a three dimensional surface, for example by moulding. 
     
     
         17 . A method for forming an article by moulding of a pulp material, the method comprising:
 moulding the article on the surface of a mould tool;   pressing the moulded article; and,   subjecting the pressed article to microwave energy whilst the pressed article is retained on a tool.   
     
     
         18 . An apparatus for forming an article, the apparatus comprising:
 a mould tool onto which pulp material is coated to form the article;   a press tool for pressing the moulded article;   a microwave energy source; and   a microwave tool on which the pressed article is retained whilst microwave energy is applied to the article.